Advances and prospect in herpesviruses infections after haematopoietic cell transplantation: closer to the finish line?

Background: Herpesviruses represent common and significant infectious complications after allogeneic haematopoietic cell transplantation (HCT). In the last decade, major advances in the prevention and treatment of these infections were accomplished. Objectives: The aim of this paper is to review the recent advances in the prophylaxis and treatment of herpesvirus infections after allogeneic HCT, to assess the persisting challenges, and to offer future directions for the prevention and management of these infections. Sources: We searched PubMed for relevant literature regarding specific herpesviruses complicating allogeneic HCT through March 2024. Content: The largest advances in this past decade were witnessed for cytomegalovirus (CMV) with the advent of letermovir for primary prophylaxis and the development of maribavir as an option for refractory and/or resistant CMV infections in transplant recipients. For varicella zoster virus, prevention of reactivation with the recombinant zoster vaccine offers an additional prophylactic intervention. Pritelivir is being explored for the treatment of drug-resistant or refractory Herpes simplex virus infections. Although rituximab is now an established option for preemptive therapy for Epstein-Barr virus, Human Herpesvirus-6 remains the most elusive virus of the herpesvirus family, with a lack of evidence supporting the benefit of any agent for prophylaxis or for optimal preemptive therapy. Implications: Although considerable advances have been achieved for the treatment and prevention of herpes virus infections, most notably with CMV, the coming years should hold additional opportunities to tame the beast in these herpesviruses postallogeneic HCT, with the advent of new antivirals, cell-mediated immunity testing, and cytotoxic T lymphocytes infusions.